Carbon nanotubes as nanoscale probes of the superconducting proximity effect in Pd-Nb junctions
| Title | Carbon nanotubes as nanoscale probes of the superconducting proximity effect in Pd-Nb junctions |
| Publication Type | Journal Article |
| Year of Publication | 2009 |
| Authors | Tselev, A., Yang Y. F., Zhang J., Barbara P., and Shafraniuk S. |
| Journal | Physical Review B |
| Volume | 80 |
| Issue | 5 |
| Pagination | 054504 |
| Abstract | We study carbon nanotubes (CNTs) connected to Nb superconducting electrodes through a thin (less than 5 nm) Pd layer. We show that the carbon nanotubes form nanoscale point contacts detecting superconducting proximity effect via Andreev reflection, where an electron injected from the nanotube is reflected as a hole at the Pd/Nb interface and a Cooper pair forms in the Nb. Our data cannot be quantitatively explained by a single interface model, where only one interface between the CNT and a superconducting electrode is considered. Instead, we present a quantitative analysis that includes two separate interfaces-CNT/Pd and Nb/Pd-at each end of the CNT. The data can be used to determine the transparencies of the Pd/Nb and CNT/Pd interfaces. |